With all due respect if someone is asking 'how do I get more power out of my car' I suspect they'd better leave the hood closed on it and learn to struggle along with only 450 hp.
I sure am! Just got mine from an(other) old guy, less than 31,000 miles and it's been lovingly cared for. Other than a trip he made from IN to ID, I doubt it's ever been in the rain.
Hope you've made progress at finding a buyer. Would be helpful if you told what kind of transmission it's got.
I'm not in the market myself, already have one... but good luck.